Railings look like a design choice, but most of what makes a stair safe is set by the building code. In Alberta, houses are built to the National Building Code – 2023 Alberta Edition (NBC(AE)). Below are the key residential numbers, with the code article for each so you or your inspector can check them. This is a homeowner summary, not a substitute for the code or your municipality's interpretation.
Handrails vs. guards
They are two different things, and people mix them up all the time:
- A handrail is what you hold while you walk up or down. Its job is grip and balance.
- A guard is the barrier that stops you falling off the open side of a stair, landing or upper floor. Its job is to stop a fall.
On many stairs one assembly does both jobs, but each has its own height rule.
The key numbers
| Rule | Requirement (NBC(AE) 2023) | Article |
|---|---|---|
| Handrail height | 865 mm to 1,070 mm (about 34" to 42") above the stair nosing | 9.8.7.4 |
| When a handrail is needed | Interior stairs with more than two risers need a handrail | 9.8.7.1 |
| Handrail supports | Fastened within 300 mm of the ends and no more than 1.2 m apart | 9.8.7.7 |
| When a guard is needed | Where the drop beside a stair, landing or floor is more than 600 mm | 9.8.8.1 |
| Guard height inside a dwelling | At least 900 mm | 9.8.8.3 |
| Guard height elsewhere | At least 1,070 mm | 9.8.8.3 |
| Openings in a guard | Must not let a 100 mm sphere pass through | 9.8.8.5 |
The 100 mm sphere rule is why spindles are spaced so closely. If a 4" ball fits through a gap between balusters, or under the bottom rail, the guard fails.
Common mistakes we see on Calgary stairs
- Basement stairs with no handrail. Plenty of older Calgary basements have a stair with three or more risers and nothing to hold. That needs fixing when you develop the basement.
- Gaps that grew. Replacing round spindles with square ones, or adding a thicker newel, can change spacing. Measure against the 100 mm rule before you order parts.
- A rail that's too low after new flooring. Adding thicker flooring or tile to treads raises the walking surface, which shortens the handrail and guard heights measured from it.
- Climbable designs. Horizontal "ladder" style infill looks modern, but the code limits elements that make a guard easy for a child to climb. Check the current wording with your inspector before choosing a horizontal design.
Do you need a permit to replace a railing?
A like-for-like railing or spindle swap is usually treated as a repair. A new stair, a relocated stair or a stair built as part of a basement development falls under that project's building permit. In Calgary, the City's basements page explains when a building permit is needed, and the framing inspection happens before walls are closed. If you're unsure, ask the City's Technical Assistance Centre before you start.
How we approach a railing job
We measure the stair first: rise, run, nosing and existing rail height. Then we plan the new balusters, newels and handrail so they meet the numbers above and look right. See our stairs and railings service or request a quote.
Frequently asked questions
What is the minimum guard height in a house in Alberta?
900 mm inside a dwelling unit and 1,070 mm in other locations, under NBC(AE) 2023 article 9.8.8.3. Some exterior locations have their own rules, so check your exact case.
How far apart can balusters be in Alberta?
Openings in a guard must not allow a 100 mm (about 4") sphere to pass through (article 9.8.8.5).
Do two-step stairs need a handrail?
Under NBC(AE) 2023, interior stairs with two risers or fewer do not need a handrail (article 9.8.7.1).
How high should a stair handrail be?
Between 865 mm and 1,070 mm, measured vertically from a line through the stair nosings (article 9.8.7.4).
Sources
- 1to1 Plans Calgary: Stair requirements in Alberta (NBC(AE) 2023)
- City of Medicine Hat: 2023 residential secondary suite information (PDF)
- City of Calgary: Home renovations and basements
Rules, programs and prices change. Always confirm details with the source before you plan or budget.
